From: Zhang Yi Date: Tue, 13 Aug 2024 12:34:50 +0000 (+0800) Subject: ext4: make extent status types exclusive X-Git-Tag: v6.12-rc1~117^2~48 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ce09036ea4f0a54e9dcd7ba644bb1db7cf2d95d4;p=thirdparty%2Fkernel%2Fstable.git ext4: make extent status types exclusive Since we don't add delayed flag in unwritten extents, all of the four extent status types EXTENT_STATUS_WRITTEN, EXTENT_STATUS_UNWRITTEN, EXTENT_STATUS_DELAYED and EXTENT_STATUS_HOLE are exclusive now, add assertion when storing pblock before inserting extent into status tree and add comment to the status definition. Suggested-by: Jan Kara Signed-off-by: Zhang Yi Link: https://patch.msgid.link/20240813123452.2824659-11-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o --- diff --git a/fs/ext4/extents_status.h b/fs/ext4/extents_status.h index 3ca40f0189947..7d7af642f7b26 100644 --- a/fs/ext4/extents_status.h +++ b/fs/ext4/extents_status.h @@ -42,6 +42,10 @@ enum { #define ES_SHIFT (sizeof(ext4_fsblk_t)*8 - ES_FLAGS) #define ES_MASK (~((ext4_fsblk_t)0) << ES_SHIFT) +/* + * Besides EXTENT_STATUS_REFERENCED, all these extent type masks + * are exclusive, only one type can be set at a time. + */ #define EXTENT_STATUS_WRITTEN (1 << ES_WRITTEN_B) #define EXTENT_STATUS_UNWRITTEN (1 << ES_UNWRITTEN_B) #define EXTENT_STATUS_DELAYED (1 << ES_DELAYED_B) @@ -51,7 +55,9 @@ enum { #define ES_TYPE_MASK ((ext4_fsblk_t)(EXTENT_STATUS_WRITTEN | \ EXTENT_STATUS_UNWRITTEN | \ EXTENT_STATUS_DELAYED | \ - EXTENT_STATUS_HOLE) << ES_SHIFT) + EXTENT_STATUS_HOLE)) + +#define ES_TYPE_VALID(type) ((type) && !((type) & ((type) - 1))) struct ext4_sb_info; struct ext4_extent; @@ -156,7 +162,7 @@ static inline unsigned int ext4_es_status(struct extent_status *es) static inline unsigned int ext4_es_type(struct extent_status *es) { - return (es->es_pblk & ES_TYPE_MASK) >> ES_SHIFT; + return (es->es_pblk >> ES_SHIFT) & ES_TYPE_MASK; } static inline int ext4_es_is_written(struct extent_status *es) @@ -228,6 +234,8 @@ static inline void ext4_es_store_pblock_status(struct extent_status *es, ext4_fsblk_t pb, unsigned int status) { + WARN_ON_ONCE(!ES_TYPE_VALID(status & ES_TYPE_MASK)); + es->es_pblk = (((ext4_fsblk_t)status << ES_SHIFT) & ES_MASK) | (pb & ~ES_MASK); }